Root on A string
x-9-10-9-10-x
F♯m7♭5 is the F♯ half-diminished chord. Its notes are F♯, A, C and E. It is the same chord as G♭m7♭5. Also written ø7. Often the ii chord in a minor ii–V–i progression.
x-9-10-9-10-x
Numbers show frets from the low E string to the high e string; x means don't play that string.
F♯m7♭5 is the viiø7 chord in G major. That makes it a natural fit in songs written in those keys.
Every F♯, A, C and E on the first 12 frets. The filled dots are the root, F♯. Build your own shape from any nearby group.
Other F♯ chords
Other half-diminished chords